Rapid early warning system and method for abnormal state of rigid suspender of high-speed railway arch bridge
Technical Field
The invention belongs to the technical field of health monitoring of bridge engineering structures, and particularly discloses a system and a method for quickly warning abnormal states of a rigid suspender of a high-speed railway arch bridge.
Background
The high-speed railway in China has been vigorously developed in recent years, and the construction speed and scale are the most important in the world. By the end of 2016, the operating mileage of the Chinese high-speed railway exceeds 2.2 kilometers. The high-speed train has the characteristics of large transportation capacity, high transportation speed, fixed running track and the like, and has important economic and strategic significance; therefore, it is necessary to pay attention to the service safety of the high-speed rail and its subsidiary facilities. As an important infrastructure for high-speed railways to cross rivers and valleys, China builds a large number of large-span high-speed railway bridges. In order to ensure the high-speed and safe operation of the high-speed train and avoid accidents, a set of quick early warning system for the abnormal service state of the high-speed railway arch bridge and key components thereof needs to be researched.
The rigid suspender arch bridge is increasingly used in a large-span high-speed railway bridge due to good lateral rigidity, the rigid suspender is one of key stress components, and under the combined action of train load, temperature, wind, local wind caused by running of a high-speed train and the like, an abnormal service state which influences the running safety of the high-speed train may occur in service. The abnormal state of the rigid suspender can be timely found at the initial stage of the abnormal state of the rigid suspender, and the method has important significance for ensuring the running safety of the rigid suspender of the high-speed railway arch bridge and the high-speed railway train.
At present, related researches on a method and a system for quickly warning the abnormal state of a rigid suspender of a high-speed railway arch bridge are not common. The invention provides a quick early warning method for the abnormal state of a rigid suspender based on structural health monitoring data of a high-speed railway arch bridge, which can find the abnormal service state of the rigid suspender in time and give an alarm and is beneficial to ensuring the normal service of the rigid suspender and the safe operation of a train.
Disclosure of Invention
The invention provides a rapid early warning method for an abnormal state of a rigid suspender of a high-speed railway arch bridge, and establishes a rapid early warning system for the abnormal state of the rigid suspender of the high-speed railway arch bridge based on the method, which is used for ensuring the normal service of the rigid suspender of the high-speed railway arch bridge and the running safety of a high-speed railway train.
The technical scheme of the invention is as follows:
a high-speed railway arch bridge rigid suspender abnormal state rapid early warning system and a method thereof, wherein the system comprises a vibration data acquisition and transmission subsystem, a data calculation and analysis subsystem and a rapid early warning subsystem; the vibration data acquisition and transmission subsystem consists of a sensor and a data transmission line which are arranged on a high-speed railway arch bridge structure; the data calculation and analysis subsystem carries out calculation and analysis based on a standard service state library established by measured data of the hanger rod in a normal service state, and rapidly evaluates the service state of the hanger rod; after the abnormal state of the suspender is found, the quick early warning subsystem calls the early warning module to alarm the bridge manager in a mode of turning on an alarm lamp, dialing an alarm call to the manager or sending an alarm short message.
The method for quickly warning the abnormal state of the rigid suspender of the high-speed railway arch bridge comprises two stages: the method comprises the following steps of establishing a standard service state library of a suspender and quickly early warning the abnormal state of the suspender:
selecting actual measurement data of one or two years before the bridge is built as actual measurement data of the normal service state of the suspender to build a standard service state library of the suspender;
the method for establishing the standard service state library of the suspender comprises the following steps:
acquiring the transverse displacement of a rigid suspender to be monitored of a high-speed railway arch bridge, the transverse strain of two sides of the section of the rigid suspender and the temperature of the same arch of the rigid suspender, and transmitting the acquired data to a data calculation and analysis subsystem in a computer;
step two, taking the variation amplitude of the transverse dynamic bending moment of the non-vehicle suspender and the variation amplitude of the transverse outer dynamic strain of the non-vehicle suspender as the service state evaluation indexes of the suspender, respectively defining the variation amplitude of the transverse dynamic bending moment or the transverse outer dynamic strain of the non-vehicle suspender as the average value of the first x maximum values in the absolute values of the variation values of the transverse dynamic bending moment or the transverse outer dynamic strain data relative to the average value of the non-vehicle transverse dynamic bending moment or the transverse outer dynamic strain data, and determining x according to the following rules: is provided with x1The absolute value of the change value of the data point of the transverse dynamic bending moment or the transverse outside dynamic strain of the suspension rod with the value more than or equal to 99 percent when the vehicle is not in use has x2The absolute value of the change value of the data point of the transverse dynamic bending moment or the transverse outside dynamic strain of the suspension rod without the vehicle with the value more than or equal to 99.9 percent is x1And x2An integer between is taken as x, i.e. x2<x<x1(ii) a The amplitude of the change of the transverse dynamic bending moment of the suspender without the vehicle is calculated according to the formula (1), wherein delta epsilon and E, I, h are respectively the transverse both-side strain variation, the elastic modulus, the section inertia moment and the section height of the cross section of the suspender:
M=ΔεEI/h (1)
Then, considering the influence of environmental wind and temperature factors on the service state evaluation index of the suspender, and extracting the service state evaluation index of the suspender in a normal service state and specific values of various influencing factors; when the influence of the temperature on the change amplitude of the transverse outer dynamic strain of the non-vehicle suspender is analyzed, the temperature data of the same side of the cross section of the suspender is extracted, and when the influence of the temperature on the change amplitude of the transverse dynamic bending moment of the non-vehicle suspender is analyzed, the temperature data of the two transverse sides of the suspender is extracted and the average value of the temperature data is obtained;
step three, in order to clearly describe the influence of certain factors in temperature and environmental wind on the service state evaluation index of a certain component, firstly eliminating the interference of other factors: when the temperature changes at 1 ℃ above and below a certain temperature, the influence of the temperature factor is considered to be ignored, and the numerical value is defined as a difference interval value; calculating the ratio of the amplitude of the transverse dynamic displacement of the suspension rod when the vehicle exists or not, and the ratio is called the ratio of the amplitude of the change for short; when a vehicle passes, the amplitude of the change of the transverse dynamic displacement of the suspender is the maximum absolute change value of the transverse dynamic displacement of the suspender during one-time passing; the transverse dynamic displacement change amplitude of the suspension rod when no vehicle is in a vehicle state is the average value of the front y maximum values in the absolute value of the change value of the transverse dynamic displacement data relative to the average value of the transverse dynamic displacement data when no vehicle is in a vehicle state, and the selection criterion of y is as follows: is provided with y1The absolute value of the change value of the transverse dynamic displacement data point of the suspension rod without the vehicle with the value more than or equal to 99 percent has y2The absolute value of the data point change value of the transverse dynamic displacement data point of the suspension rod when the value is more than or equal to 99.9 percent of the data point change value of the suspension rod without the vehicle is determined in y1And y2Any integer therebetween as y, i.e. y2<y<y1(ii) a When the ratio of the change amplitudes is larger than 10, the influence of the environmental wind on the transverse vibration amplitude of the suspender is small and similar, and the influence of the environmental wind factor is eliminated;
establishing different standard service state sublibraries of the rigid suspender of the high-speed railway arch bridge based on different service state evaluation indexes by utilizing long-term monitoring data measured by the structural health monitoring system when the suspender is in a normal service state, and evaluating the service state of the rigid suspender of the high-speed railway arch bridge from different angles; considering the influence of temperature and environmental wind on the evaluation index of a certain service state of the suspender, two methods for establishing a standard service state sub-library of the rigid suspender are provided: when the standard service state sub-library of the suspender is established according to the first method, the influence of the reserved temperature on the service state evaluation index of the suspender is eliminated, and when the standard service state sub-library of the suspender is established according to the second method, the influence of the temperature and the environmental wind on the service state evaluation index of the suspender is eliminated; the two establishing methods comprise the following steps:
the first establishing method of the suspender standard service state sublibrary comprises the following steps:
(1) extracting a suspender service state evaluation index and corresponding temperature data based on the long-term monitoring data;
(2) the influence of environmental wind factors is eliminated through setting the ratio of the variable amplitude values;
(3) obtaining a specific value of the evaluation index of the service state of the suspender, which is only influenced by the temperature, and storing the specific value into a standard service state sub-library of the suspender;
the second method for establishing the standard service state sublibrary of the suspender comprises the following steps:
(1) extracting a suspender service state evaluation index and corresponding temperature data based on the long-term monitoring data;
(2) the influence of environmental wind factors is eliminated through setting the ratio of the variable amplitude values;
(3) obtaining a statistical relation of the influence of the temperature on the service state evaluation index of the suspender, and carrying out regression analysis on the statistical relation based on a least square method to obtain a fitting line of the influence of the temperature on the service state evaluation index of the suspender;
(4) and eliminating the trend of the influence of the temperature on the service state evaluation index of the suspender according to the fit line, and storing the service state evaluation index of the suspender after the trend item is removed into a standard service state sub-library of the suspender.
The method comprises the following steps of providing an early warning standard of an abnormal service state of a suspender based on an established suspender standard service state sub-library to perform quick early warning of the abnormal state of the suspender, wherein the method comprises the following steps:
step one, determining an early warning envelope line or an early warning threshold line by considering safety margin based on an established standard service state sub-library; the early warning envelope line is an envelope line with safety margin when the standard service state library of the suspender is established by adopting a first establishing method of the standard service state sub-library of the suspender, and is obtained by taking the safety margin into consideration by an outer envelope line of data points in the standard service state library of the suspender; the early warning threshold line is a threshold line with safety margin when the standard service state library of the suspender is established by adopting a second establishing method of the standard service state sub-library of the suspender, and the value of the early warning threshold line is the sum of the maximum absolute value of the data point of the standard service state library and the safety margin;
secondly, calculating the current service state evaluation index value of the corresponding rigid suspender by adopting a method the same as the service state evaluation index in the standard service state library based on the current real-time monitoring data of the high-speed railway arch bridge structure to be measured;
step three, comparing the current service state evaluation index value with a corresponding early warning envelope line or a threshold line, and if the data point of the current service state evaluation index value falls outside the early warning envelope line or the current service state evaluation index value is larger than the early warning threshold value, judging that the rigid suspender is in an abnormal service state;
and step four, once the hanger rod is found to be in an abnormal state, automatically starting the quick early warning subsystem to call the early warning module, and immediately warning by adopting a method of starting a warning lamp, dialing an alarm call to a mobile phone of a manager or sending an alarm short message, so that the manager is ensured to find the abnormal hanger rod in time and take treatment measures according to the situation.
The system has the advantages that the real service state of the suspender can be automatically evaluated on line, the abnormal state of the suspender can be found in time, the manpower can be greatly saved, the early warning efficiency is improved, and the safety service of the rigid suspender of the high-speed railway arch bridge and the driving safety of a high-speed railway train can be ensured.
Drawings
FIG. 1 is a schematic diagram of the system of the present invention.
FIG. 2 is a schematic view of the arrangement of the boom and the measuring point to be monitored.
Fig. 3 is a flow chart of boom standard in-service state library establishment.
FIG. 4 is a suspender transverse dynamic bending moment standard service state sub-library and an early warning enveloping diagram thereof, which are established based on the first establishing method of the suspender standard service state sub-library.
FIG. 5 is a graph of the relationship and fit line of temperature to amplitude of change in lateral outboard dynamic strain of the hanger bar without the vehicle.
FIG. 6 is a diagram of a boom lateral outside dynamic strain standard service state sub-base and its early warning threshold value, which are established based on the second establishing method of the boom standard service state sub-base.
Fig. 7 is a flow chart of early warning of an abnormal state of a rigid suspender of a high-speed railway arch bridge.
Detailed Description
Fig. 1 is a schematic diagram of the system of the present invention, and the present invention will be further described with reference to the accompanying drawings and specific embodiments.
Taking a certain two high-speed railway arch bridges as an example, the bridge main span is provided with two train tracks and 21 suspenders; taking one suspender as an example, the specific implementation mode of the system is introduced through the quick early warning of the abnormal state of the suspender. The example boom is set to be a # 1 boom with the position and station arrangement as in figure 2.
(1) Mounting vibration data acquisition and transmission subsystem
Considering the need of acquiring the service state evaluation data of the suspender for a long time, as shown in fig. 2, transverse displacement measuring points are arranged on the transverse outer side of the 1# suspender, strain measuring points are respectively arranged on the transverse two sides of the cross section of the 1# suspender, and temperature measuring points are respectively arranged on the same sides of the strain measuring points; and the collected data is transmitted to the data calculation and analysis subsystem.
(2) Determining jib service state evaluation index
According to the vibration characteristic of the rigid hanger rod of the high-speed railway arch bridge, the transverse dynamic bending moment variation amplitude of the hanger rod without the vehicle and the transverse outer dynamic strain variation amplitude of the hanger rod without the vehicle are selected as the service state evaluation indexes of the short hanger rod for illustration. The service index extraction method of the two suspenders is as follows:
1) extraction of transverse dynamic bending moment variation amplitude of suspender during no vehicle
Firstly, preprocessing data of dynamic strain on two transverse sides of a suspender, which is acquired by strain measuring points on the suspender; then, calculating the transverse dynamic bending moment of the suspender according to the formula (1); and finally, taking the average value of the first 100 maximum absolute change values from the transverse moving bending moment of the non-vehicle lifting rod calculated before the vehicle passes once as the transverse moving bending moment change amplitude of the non-vehicle lifting rod before the vehicle passes once, wherein x is 100.
2) Extraction of dynamic strain change amplitude of transverse outer side of suspender during non-vehicle
Firstly, carrying out data preprocessing on the lateral outer dynamic strain acquired by a suspender strain measuring point; and then, extracting the transverse outer dynamic strain value of the front suspender after the vehicle passes once, and taking the average value of the first 100 maximum absolute change values as the transverse outer dynamic strain change amplitude of the front suspender without the vehicle before the vehicle passes once, wherein x is 100.
(3) Establishing a standard service state library of a suspender
Based on actual measurement data of the bridge in the previous year after the bridge is built, a 1# suspender transverse dynamic bending moment standard service state sub-library is built by using a first building method of a suspender standard service state sub-library and taking a non-vehicle suspender transverse dynamic bending moment variation amplitude as a service state evaluation index; and (3) taking the transverse outer dynamic strain change amplitude of the non-vehicle suspender as a service state evaluation index, and establishing a 1# suspender transverse outer dynamic strain standard service state sub-library by adopting a second establishing method of a suspender standard service state sub-library. The boom standard service state library establishing process is shown in fig. 3, and specifically comprises the following establishing steps:
1) establishing a 1# suspender transverse dynamic bending moment standard service state sub-warehouse
Extracting the transverse dynamic bending moment change amplitude of the suspender and corresponding temperature data when no vehicle exists based on the long-term measured data; the influence of the environmental wind is eliminated through setting the ratio of the variable amplitude values; and obtaining the variation amplitude of the transverse dynamic bending moment of the suspender without the vehicle, which is only influenced by the temperature, and storing the variation amplitude into a standard service state sublibrary of the transverse dynamic bending moment of the suspender, as shown in figure 4.
2) Establishing a 1# suspender transverse outside dynamic strain standard service state sub-library
Extracting the transverse outer side dynamic strain change amplitude of the suspender and corresponding temperature data when no vehicle exists based on the long-term measured data; the influence of environmental wind factors is eliminated through setting the ratio of the variable amplitude values; obtaining a statistical relation of the influence of the temperature on the amplitude of the dynamic strain change of the transverse outer side of the suspender without the vehicle and obtaining a fitting line of the statistical relation, as shown in figure 5; and eliminating the trend of the influence of the temperature on the change amplitude of the transverse outer side dynamic strain of the hanger rod when the vehicle is absent according to the trend removing item of the fit line, and storing the change amplitude of the transverse outer side dynamic strain of the hanger rod after the trend removing item, namely the change standard value of the transverse outer side dynamic strain of the hanger rod when the vehicle is absent into a service state sub-library of the transverse outer side dynamic strain standard of the hanger rod, as shown in figure 6.
(4) Early warning process of abnormal state of rigid suspender (fig. 7)
1) Suppose that the 1# boom is in an abnormal state due to extreme environmental effects or damage. Based on the measured data, the estimation index value of the service state of the suspender is extracted, and in the example, the estimation index value is the variation amplitude of the transverse dynamic bending moment of the suspender without vehicle or the variation amplitude of the transverse outer side dynamic strain of the suspender without vehicle.
2) The temperature and the environmental wind effect at the moment are quickly determined based on the measured data, and the corresponding boom standard service state sub-base established by two establishing methods based on the boom standard service state sub-base is called according to the factors, wherein an early warning envelope line or an early warning threshold value is determined according to 10% of safety margin in the example, which is detailed in figures 4 and 6. Meanwhile, the current suspender service state evaluation index value is calculated based on the current measured data. And comparing the current evaluation index value of the service state of the suspender with the early warning envelope line or the early warning threshold value, and finding that the data point of the currently calculated transverse dynamic bending moment change amplitude of the non-vehicle suspender falls outside the early warning envelope line and the transverse outer dynamic strain change amplitude of the non-vehicle suspender exceeds the early warning threshold value at the moment.
3) And starting the quick early warning subsystem, calling the early warning module, and enabling bridge managers to find abnormal service states of the rigid suspender in time and take corresponding measures in time by adopting a mode of starting an alarm lamp, making a call to a mobile phone of the manager or sending an alarm short message.
The method provided by the invention can monitor the service state of the rigid suspender of the high-speed railway arch bridge, discover the abnormal suspender in time and give an alarm, and has important significance for the rigid suspender of the high-speed railway arch bridge and the running safety of a high-speed railway train.